F. Galaz-Fontes (Proc. AMS., 1998) has established a criterion
for a subset of the space of compact linear operators from a reflexive and
separable space X into a Banach space Y to be compact. F. Mayoral (Proc.
AMS., ...

In this paper, the Hyers-Ulam stability of the Volterra integrodifferential equation and the Volterra equation on the finite interval [0, T], T > 0, are studied, where the state x(t) take values in a Banach space X.

This paper contains constructions of some non-measurable sets,
based on classical Vitali’s and Bernstein’s constructions (see for example [6]).
This constructions probably belong to mathematical folklore, but as far ...

A simple age-dependent population dynamics model with an additional structure or physiological variable is presented in its variational formulation. Although the model is well-posed, the closed form solution with space ...

Here in this paper we intend to deal with two questions: How large is a “Lebesgue Class” in the topology of Lebesgue integrable functions, and also what can be said regarding the topological size of a “Lebesgue set” in R?, ...

In this paper there has been investigated a set of values of a mapping connected with a maximal value of the functional |a_3 - aα_2^2| in
the well-known class S of functions holomorphic and univalent in the
unit disc ...

A new definition of the topological entropy of a foliation is introduced
in this paper. This definition is slightly different from the definition
of the topological entropy of a foliation given by E. Ghys, R. Langevin, ...